US7454227B2 - Wireless communication module, communication terminal, and impedance matching method - Google Patents

Wireless communication module, communication terminal, and impedance matching method Download PDF

Info

Publication number
US7454227B2
US7454227B2 US11/263,073 US26307305A US7454227B2 US 7454227 B2 US7454227 B2 US 7454227B2 US 26307305 A US26307305 A US 26307305A US 7454227 B2 US7454227 B2 US 7454227B2
Authority
US
United States
Prior art keywords
transmission power
matching
antenna
wireless communication
transmitter
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related, expires
Application number
US11/263,073
Other versions
US20060094458A1 (en
Inventor
Mitsuhiro Kitaji
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
HANEI Corp
Original Assignee
Kyocera Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kyocera Corp filed Critical Kyocera Corp
Assigned to KYOCERA CORPORATION reassignment KYOCERA CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KITAJI, MITSUHIRO
Publication of US20060094458A1 publication Critical patent/US20060094458A1/en
Application granted granted Critical
Publication of US7454227B2 publication Critical patent/US7454227B2/en
Assigned to HANEI CORPORATION reassignment HANEI CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KYOCERA CORPORATION
Expired - Fee Related legal-status Critical Current
Adjusted expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/06—Receivers
    • H04B1/16—Circuits
    • H04B1/18—Input circuits, e.g. for coupling to an antenna or a transmission line
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
    • H04W52/04—TPC
    • H04W52/06—TPC algorithms
    • H04W52/08—Closed loop power control
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/02—Transmitters
    • H04B1/04—Circuits
    • H04B1/0458—Arrangements for matching and coupling between power amplifier and antenna or between amplifying stages
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/06—Receivers
    • H04B1/10—Means associated with receiver for limiting or suppressing noise or interference
    • H04B1/12—Neutralising, balancing, or compensation arrangements
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
    • H04B1/40—Circuits
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B17/00—Monitoring; Testing
    • H04B17/10—Monitoring; Testing of transmitters
    • H04B17/101—Monitoring; Testing of transmitters for measurement of specific parameters of the transmitter or components thereof
    • H04B17/102—Power radiated at antenna
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B17/00—Monitoring; Testing
    • H04B17/10—Monitoring; Testing of transmitters
    • H04B17/15—Performance testing
    • H04B17/18—Monitoring during normal operation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/02—Transmitters
    • H04B1/04—Circuits
    • H04B2001/0408—Circuits with power amplifiers
    • H04B2001/0416—Circuits with power amplifiers having gain or transmission power control

Abstract

A wireless communication module for engaging in communications with a base station, the wireless communication module being incorporated into an information device having an antenna, includes a transmitter, a transmission power being controlled by the base station; variable impedance matching section arranged between an antenna connector connected to the antenna and the transmitter, which adjusts an impedance by changing a matching parameter for the variable impedance matching section; transmission power detector for detecting the transmission power; and a controller for adjusting the matching parameter based on the detected transmission power of the transmitter detected by the transmission power detector.

Description

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a wireless communication module, a communication terminal, and an impedance matching method. More specifically, the present invention relates to technology of matching impedance with an antenna in a wireless communication module incorporated into an information device (for example, a PDA).
Priority is claimed on Japanese Patent Application No. 2004-318019, filed Nov. 1, 2004, the content of which is incorporated herein by reference.
2. Description of the Related Art
In a communication terminal such as a portable mobile phone in which an antenna is equipped, in gene, circuits are designed so as to match an antenna with an RF circuit (radio amplifying circuit) in a range of the frequencies used. In wireless communication modules, a matching circuit is typically designed so as to be incorporated into an information device. Since there may be a mismatch due to the influence of objects placed around the antenna in these communication terminals and wireless communication modules, matching circuit technology having an automatic matching capability has been proposed.
According to conventional techniques, for example, in a portable wireless communication device provided with an electric power detecting device, a device for detecting a phase of a reflected signal from the antenna, and a matching circuit for adjusting a variable impedance to match between the antenna and an RF circuit, reflection phase from the antenna and input electric power into the antenna are compared with a reference value, thereby obtaining an optimal matching. The portable wireless communication device measures a reflection phase SP from the antenna and a consumption current S1 supplied to the antenna using a phase detector and an ammeter to compare them with SP0 and S10 measured in advance in a matched state, thereby attaining matching by adjusting the matching circuit repeatedly when these values deviate from the pre-measured values (refer to Japanese Unexamined Patent Application, First Publication No. 2003-174367).
Furthermore, some antenna circuits have a plurality of matching circuits, by which the transmission level is detected in front of the antenna to switch the matching circuits so that the transmission level can be maximized. These antenna circuits are designed to select a matching circuit so as to maximize the transmission level at a level-detecting portion installed closest to the matching circuits.
Furthermore, some impedance matching devices are provided with a variable impedance matching portion installed between a transmitting portion and an antenna, a standing wave ratio detecting portion, a voltage phase detecting portion, an impedance calculating portion and the like to detect the voltage standing wave ratio (VSWR) of transmission waves, thereby obtaining matching. Such impedance matching devices measure an impedance of the antenna with respect to a transmission channel and calculate a difference between the thus-measured impedance and an impedance Z0 at the transmitting portion to be matched, thereby attaining matching and also obtaining matching parameters in this instance.
In the above-described conventional technique, impedance matching requires an addition of a phase detecting circuit, a voltage standing wave ratio (VSWR) detecting circuit and the like to the circuit, resulting in problems such as increased size of the communication terminal and the like.
There is another problem in that in a wireless communication module for engaging in communications so as to be incorporated into an information device, impedance is set in advance to a predetermined value (for example, 50Ω) and the impedance deviates from the predetermined value due to electromagnetic influence from the incorporated information device, thereby making it impossible to carry out accurate impedance matching.
SUMMARY OF THE INVENTION
The present invention has been made for solving these problems and provides a wireless communication module, a communication terminal, and an impedance matching method which are able to easily attain impedance matching with an antenna, when a circuit is configured at the smallest possible size and the wireless communication module is incorporated into the information device (for example, a PDA) and the like, in the wireless communication module incorporated into an information device.
The present invention has been made for solving the above problems, and a first aspect of the present invention is a wireless communication module for engaging in communications with a base station, the wireless communication module being incorporated into an information device having an antenna, including a transmitter, a transmission power being controlled by the base station; variable impedance matching section arranged between an antenna connector connected to the antenna and the transmitter, which adjusts an impedance by changing a matching parameter for the variable impedance matching section; transmission power detector for detecting the transmission power; and a controller for adjusting the matching parameter based on the detected transmission power of the transmitter detected by to transmission power detector.
With this, impedance matching with the antenna can be easily attained when the wireless communication module incorporated into the information device and the like. Furthermore, in this instance, electric power supplied to the antenna is minimized, achieving power conservation. It is not necessary to design the wireless communication module tailored to the information device as in the conventional technique. In addition, by only detecting the transmission power of the transmitter, it is possible to attain impedance matching, thereby making it possible to achieve a minimal circuit construction without addition of special circuits.
Additionally, according to a second aspect of the present invention, the controller may adjust the matching parameter when the transmission power of the transmitter detected by the transmission power detector is stable.
With this, it is possible to ensure that matching parameters with which impedance matching with the antenna can be are obtained.
Furthermore, according to a third aspect of the present invention, the wireless communication module may further include an environment detector for detecting a predetermined external environment condition; and a storage portion for storing the matching parameter, and the controller may associate the matching parameter that has been used for the adjustment of the impedance with information on the environment detected by the environment detector and store the matching parameter and the information into the storage portion.
Therefore, it is possible to immediately attain impedance matching with the antenna by reading out matching parameters from the storage portion, according to the external environment conditions.
Furthermore, according to a fourth aspect of the present invention, the wireless communication may further include a storage portion for storing the matching parameter, and the controller may obtain device-identifying information from the information device and associates the matching parameter that has been used for the adjustment of the impedance with the device-identifying information and store the matching parameter and the device-identifying information in the storage portion.
With this, it is not necessary to design a wireless communication module tailored to a type of the information device or design an information device tailored to the wireless communication module, thus making it possible to provide a general-purpose wireless communication module independent from the device into which it is to be incorporated. In addition, impedance matching with the antenna can be immediately attained by reading out matching parameters according to the device-identifying information from the storage portion.
A fifth aspect of the present invention is a communication terminal, including: a transmitter, a transmission power being controlled by a base station; a variable impedance matching section arranged between an antenna and the transmitter, which adjusts an impedance by changing a matching parameter for the variable impedance matching section; a transmission power detector for detecting the transmission power; and a controller for adjusting the matching parameter based on the detected transmission power of the transmitter detected by the transmission power detector.
With this, impedance matching with the antenna can be easily attained in a communication terminal having a simplified configuration. Furthermore, in this instance, electric power supplied to the antenna is minimized, thereby achieving power conservation, and thus resulting in an extended life of the battery, which is advantageous.
Furthermore, according to a sixth aspect of the present invention, the controller may adjust the matching parameter when the transmission power of the transmitter detected by the transmission power detector is stable.
With this, it is possible to ensue that matching parameters with which impedance matching with the antenna can be attained are obtained.
According to a seventh aspect of the present invention, the communication terminal may further include an environment detector for detecting a predetermined external environment condition; and a storage portion for storing the matching parameter, and the controller may associate the matching parameter that has been used for the adjustment of the impedance with information on the environment detected by the environment detector and store the matching parameter and the information into the storage portion.
With this, it is possible to immediately attain impedance matching with the antenna by reading out from the storage portion matching parameters, according to the external environment conditions.
An eighth aspect of the present invention is an impedance matching method for a communications device including a transmitter, a transmission power being controlled by a base station; a variable impedance matching section arranged between the antenna and the transmitter, which adjusts an impedance by changing matching parameters; and a transmission power detector for detecting the transmission power, including: performing an impedance matching by adjusting a matching parameter for the variable impedance matching section based on a detected value of the transmission power of the transmitter detected by the transmission power detectord.
With this, by only detecting the transmission power of the transmitter, it is possible to attain impedance matching, thereby making it possible to achieve a minimal circuit construction without addition of special circuits.
In the present invention, impedance matching with an antenna can be easily attained when the wireless communication module incorporated into the information device. Furthermore, in the communication terminal, impedance matching with the antenna can be easily attained, thereby minimizing electric power supplied to the antenna.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic block diagram showing a wireless communication module according to a first embodiment of the present invention;
FIG. 2 is a flowchart showing an impedance matching procedure with the antenna and the transmitting portion;
FIG. 3 is a graph showing a relationship between set values of matching parameters and the transmission power of the transmitting portion;
FIG. 4 is a flowchart showing the impedance matching procedure when the module is incorporated into the information device;
FIG. 5 is a schematic block diagram showing a wireless communication module according to a second embodiment of the present invention; and
FIG. 6 is a flowchart showing the impedance matching procedure according to external environment conditions.
 DETAILED DESCRIPTION OF THE INVENTION
Thereinafter, a description is given of the best mode for carrying out the present invention with reference to the drawings.
First Embodiment
FIG. 1 is a schematic block diagram showing a wireless communication module having an external antenna according to a first embodiment of the present invention, in which transmission power of a wireless communication module 100 is controlled by a base station (not shown) so that the transmission power from the wireless communication module 100 can be received at an appropriate level by the base station.
In FIG. 1, the wireless communication module 100 includes an antenna connection portion (antenna connector) 101, a variable impedance matching portion (variable impedance matching section) 102 having variable impedance (for example, condenser capacity and inductance) which can be adjusted, a distributor (DUP) 103 for distributing signals transmitted or received, a receiving portion (receiver) 104, a transmitting portion (transmitter) 105, a base band portion 106 for controlling communications, a control portion (controller) 107, a memory 108, a transmission power detecting portion (transmission power detector) 109 for detecting the transmission power of the transmitting portion, an external environment detecting portion (environment detector) 110 for detecting external environment conditions when the portable mobile phone is in use, and an external interface 111 for interfacing with the information device having the wireless communication module incorporated therein.
The transmission power detecting portion 109 is configured so as to detect the transmission power of the transmitting portion 105. Furthermore, the transmission power detecting portion 109 is configured so as to detect, as indicators of the transmission power, an applied voltage of a power amplifier (PA) inside the transmitting portion 105 and an applied voltage of an automatic gain control circuit (AGC) from the base band portion 106.
The external environment detecting portion 110 is configured so as to detect a how the information device having the wireless communication module 100 incorporated therein is being used (for example, a user is making a phone call with a called party by putting the portable communication terminal to an ear by hand or data communications is carried out with the terminal placed on a desk) by using, for example, various sensors.
When the wireless communication module 100 is incorporated into an information device (for example, a PDA) having an antenna, an antenna 101 a is connected to the antenna connection portion 101 and the control portion 107 executes the impedance matching procedure as described below.
FIG. 2 is a flowchart showing an impedance matching procedure of the antenna with the transmitting portion. Hereinafter, a description is given for the procedures for adjusting impedance matching in the wireless communication module shown in FIG. 1 with reference to the flowchart of FIG. 2.
First, when the wireless communication module 100 starts to communicate with the base station, the control portion 107 determines whether or not impedance matching should be executed (step S01). In this instance, such determination may be made by a user according to the conditions set by the user, or made as a process of prior adjustment in a manufacturing facility by a manufacturer rather than by a user.
When it is determined that matching should be executed in step S01, the control portion 107 then determines whether or not the transmission power detected by the transmission power detecting portion 109 is stable (step S02). The control portion 107 obtains the transmission power from the base band portion 106 and confirms that the transmission power detected by the transmission power detecting portion 109 has not been changed.
When it is determined that no matching should be executed in step S01 or the transmission power is unstable in step S02, the process does not proceed to the subsequent step S02 or S03, instead communications are executed as normal operation (step S09).
When it is determined that the transmission power is stable in step S02, the control portion 107 detects the transmission power of the transmitting portion 105 (step S03). Then, the control portion 107 controls the variable impedance matching portion 102 to change the impedance of the variable impedance matching portion 102 (step S04). In this instance, matching parameters should be stored into the memory (storage portion) 108.
As matching changes in the variable impedance matching portion 102, transmission power of the antenna 101 a is changed. The change in matching to an improved match results in a better transmission efficiency from the transmitting portion 105 to the antenna 101 a to suppress a reflected wave, thereby increasing the transmission power of the antenna 101 a. The change in matching to a worsened match results in a reduction in the transmission power.
According to the change in the transmission power, the base station controls the transmission power of the wireless communication module 100 (step S05). When the transmission power is increased due to an improved match, the power is controlled so as to be decreased to compensate for the increase. When the transmission power is decreased, the transmission power is controlled so as to be increased to compensate for the decrease. This step either increases or decreases the transmission power of the transmitting portion 105. The transmission power detecting portion 109 again measures the transmission power of the transmitting portion 105 (S06).
Then, the steps S04 to S06 are executed to make a determination on whether or not matching parameters have been obtained which minimize the transmission power of the transmitting portion 105 (step S07). When the determination in step S07 is NO, the process returns to step S04 to make readjustment. This process is repeated until the determination in step S07 is YES. In the course of the iteration, matching parameters for the variable impedance matching portion 102 are adjusted and the transmission power of the transmitting portion 105 is measured, during which the control portion 107 determines matching parameters for the variable impedance matching portion 102 which minimize the transmission power of the transmitting portion 105.
Here, a description is given for determining a minimum value of the transmission power by changing matching parameters. In this instance, a matching parameter for the variable impedance matching portion 102 is given as x and a transmission power of the transmitting portion 105 is given as y. When x is an optimal value, y is minimized. When these optimal values are given as x0 and y0, y is greater than y0 regardless of whether x becomes greater or smaller than x0, and y is greater in value as the difference between x and x0 is greater.
Therefore, ideally, it is considered that that y may be a quadratic function of x in the vicinity of x0 as shown in FIG. 3. At this time, matching parameters may be changed N times at random in the range set by appropriate values, y obtained each time is stored into the memory 108 together with x, and the value of x which gives a minimum value of y at the time of completion of N iterations may be used. Alternatively, y may be measured at two appropriate points for x to calculate the slope therebetween until the slope becomes zero, and when the slope is zero, a median point may be obtained for these two points of x to give a minimum value. Alternatively, the slope may be calculated at x and x+Δx, and if the slope is a positive value, x may be deceased, whereas if the slope is a negative value, x may be increased. Then, measurement of the slope of x and x+Δx is done again, and this process is repeated to determine the x when the slope becomes zero.
Furthermore, it may be possible that when a settable minimum value of a matching parameter x is given as xmin and a settable maximum value is given as xmax, x be allowed to change with an adjustable minimum increment or decrement from xmin to xmax, and x at the time when a minimum value of the transmission power y is obtained in each step is given as a matching parameter x0 for which the transmission power is minimized. In this method, since the detection time of the transmission power y is dependant on an adjustable minimum increment or decrement of x and an adjustable range of x, it is ensured that a matching parameter x0 can be determined in the settable range of x, although it may require some time to determine the matching parameter x0.
When in step S07 a minimum value of the transmission power of the transmitting portion 105 is determined and the determination is YES, a matching parameter at the time when a minimum value of the transmission power is obtained is set for the variable impedance matching portion 102 (step S08). When the setting is completed, adjustment of the variable impedance matching portion 102 is completed to continue ordinary communications (step S09).
The above-described an impedance matching procedure is executed by the control portion 107, impedance of the variable impedance matching portion 102 is adjusted so as to minimize the transmission power of the transmitting portion 105, and addition of circuits is minimized in an existing system for conducting an impedance matching, thereby making it possible to easily attain impedance matching with an antenna. Therefore, a wireless communication module can be designed without dependence on the type of information device having the wireless communication module incorporated therein and also impedance matching can be attained by a general-purpose wireless communication module independent of type of the information device having the module incorporated therein. Furthermore, in this instance, electric power supplied to the antenna is minimized, thereby achieving power consumption.
Next, a description is given for the impedance matching procedure when a wireless communication module is incorporated into an information device, such as a PDA, with reference to FIG. 4. FIG. 4 is a flowchart showing the impedance matching procedure when the wireless communication module is incorporated into an information device, such as a PDA. Furthermore, a description is given on the assumption that the information device having the module incorporated therein is a PDA.
The wireless communication module 100 (refer to FIG. 1) is incorporated into the PDA, and an antenna which is installed in the PDA is connected to an antenna connection portion 101. The PDA is connected to a control line which controls the wireless communication module 100 and an external interface 111 having a line. When the control portion 107 starts to adjust impedance matching, device-identifying information for the PDA (a serial number and the like) is obtained through the external interface 111 as a first step (step S11).
Then, the control portion 107 checks whether or not matching parameters for the thus identified PDA are stored into the memory 108 (step S12). If the matching parameters of the PDA are stored into the memory 108, the control portion 107 applies the matching parameters (step S15).
If the matching parameter is not in the memory 108, the control portion 107 conducts impedance matching by the impedance matching procedure described in the flowchart of FIG. 2 (step S13). Then, the control portion 107 stores matching parameters together with the PDA information (device-identifying information) into the memory 108 (step S14). Then, the control portion 107 applies the matching parameter to the variable impedance matching portion 102 (step S15) to complete adjustment of the matching and returns to normal operation of the information device (step S16).
It may also be possible that the control portion 107 detect external environment conditions using the external environment detecting portion 110 and make adjustments, such as impedance matching, according to the external environment conditions. In this instance, the device-identifying information, external environment conditions, and matching parameters are associated to each other and stored into the memory 108, by which matching parameters according to external environment conditions can be retrieved from the memory 108 to attain impedance matching immediately.
As described above, use of the wireless communication module in the present invention eliminates the necessity for designing a wireless communication module tailored to an information device or designing an information device tailored to the wireless communication module, thereby making it possible to provide a general-purpose wireless communication module independent of the type of information device having the module incorporated therein.
An explanation was given for the wireless communication module shown in FIG. 1 with reference to an example which is incorporated into a PDA. However, the information device having the wireless communication module incorporated therein may be any information device, including PDAs.
In addition, impedance matching with an antenna depends to some extent on conditions (external environment conditions) in which an information device and the like to which a wireless communication module is incorporated are used. Therefore, matching may be attained at any time when a user starts to make communications, or matching parameters may be stored into the memory 108, together with conditions for starting impedance matching to allow setting of corresponding matching parameters when can conditions are detected.
Second Embodiment
FIG. 5 is a schematic block diagram showing a communication terminal of a second embodiment in the present invention, showing a portable mobile phone as an example of the communication terminal. In the example shown in FIG. 5, the transmission power of a portable mobile phone 200 is controlled by a base station in such a way that the transmission power from the portable mobile phone 200 can be received at an appropriate level by the base station (not shown).
The portable mobile phone 200 includes an antenna 201, a variable impedance matching portion 202 having variable impedance which can be adjusted, a distributor (DUP) 203 for distributing signals transmitted or received, a receiving portion 204, a transmitting portion 205, a base band portion 206 for controlling communications, a control portion 207, a memory 208, a transmission power detecting portion 209 for detecting the transmission power of the transmitting portion 205, and an external environment detecting portion 210 for detecting external environment conditions when the portable mobile phone is in use.
Since the transmission power detecting portion 209 and the external environment detecting portion 110 in the present embodiment are constructed similarly to in the above first embodiment, detailed description thereof is omitted.
An impedance matching procedure of the antenna 201 with the transmitting portion 202 in the portable mobile phone 200 is the same as those explained in the flowchart of FIG. 2 in the first embodiment, by which impedance matching of the antenna 201 with the transmitting portion 205 can be easily attained in the portable mobile phone 200. Furthermore, in this instance, electric power supplied to the antenna 201 is minimized achieving power conservation, resulting in an extended lift of the battery, which is advantageous.
In addition, impedance matching with an antenna 201 depends to some extent on circumstances in which a communication terminal such as a portable mobile phone is used. Therefore, matching may be attained at any time when a user starts to make communications, or matching parameter may be stored into the memory 208, together with conditions for starting impedance matching, to allow setting of corresponding matching parameters when certain conditions are detected.
There is, for example, a device for detecting conditions such as environment conditions, of a user making a phone call by putting the mobile phone to an ear by hand, making data communications with the communication terminal placed on a desk, or making communications by using a hand-free kit, with the terminal placed on a desk, and matching parameter under these environmental conditions are stored into the memory together with the environmental conditions and the parameters are retrieved and set when the environmental conditions are detected thereafter.
A description is given for the impedance matching procedure according to the external environments with reference to the flow shown in FIG. 6.
In starting adjustment of the impedance matching, the control portion 207 detects environmental conditions in the surroundings from the external environment detecting portion 210 as a first sp (step S21). In this instance, the device for detecting the conditions includes a device for detection by using various sensors, with terminal kept in hand, put to an ear, or placed on a desk. Alternatively, matching parameters may be set to a certain value to identify a matching pattern in a specific environment in accordance with a change in the signal receiving level of an antenna.
Once environmental conditions are obtained in step S21, the control portion 207 detects the conditions obtained in step S21 and checks whether or not matching parameters at that time are available in the memory 208 in step S22.
If matching parameter corresponding to the conditions are available, the matching parameters are applied to the variable impedance matching portion 202 to attain a matching (step S25).
If no matching parameters corresponding to the conditions are available, the control portion 207 starts to make communications and adjusts matching by the impedance matching procedure explained in the flowchart of FIG. 2 in the first embodiment, thereby determining the matching parameters (step S23).
Then, the control portion 207 stores the environmental conditions and the matching parameters into the memory 208 (step S24). Thereafter, the matching parameters are applied (step S25) to complete adjustment of the matching. Then, the portable mobile phone 200 returns to normal operation (step S26).
The matching parameters in the memory 208 are stored previously for specific environmental conditions, thereby making it possible to retrieve the corresponding matching parameters to attain instant matching in the next step.
In the above second embodiment, an explanation was given for a portable mobile phone as a communication terminal, and communication terminals include mobile terminals, PDAs (Personal Digital Assistances) and the like.
As described above, a method for attaining impedance matching so as to minimize transmission power is preferably applicable to a communication system in which transmission power of a communication terminal (or a wireless communication module) in communications is controlled by a base station (for example, in a Cdma 2000 1x, or Cdma 2000 1xEV-DO, a base station dictates the transmission power of a communication terminal an electric control bit every 1/800 or 1/600 seconds, respectively, so as to keep an electric power level of the communication terminal received at the base station at a specific level). In this instance, in a stable environment, a transmission power of the antenna end of the communication terminal is kept substantially constant by controlling the transmission power by the base station. Therefore, the transmission power of the transmitting portion and voltage of a PA or an AGC are measured at this time to provide impedance matching that achieves a minimum transmission power, thereby making it possible in order to attain a matching with an antenna in a simplified configuration. Furthermore, in this instance electric power supplied to the antenna is minimized, achieving power conservation and results in an extended life of the battery, which is advantageous.
With this construction, it may be suffice to detect a transmission power of the transmitting portion (for example, voltage applied to a PA and/or an AGC), and a Cdma 2000 1x or the like permits detection of settings of the transmission power or voltage of a base band portion without addition of special circuits. This eliminates the necessity for an additional transmission power detecting circuit, requiring only addition of a variable matching circuit and the control thereof, thereby making it possible to attain impedance matching within a minimum addition of circuits. Furthermore, if the wireless communication module of the present invention is incorporated, development tasks required in the conventional art, such as the necessity for attaining matching after incorporating a wireless communication module, can be eliminated, a more general-purpose module can be provided, and also man-power required for development of each information device having the wireless communication module incorporated therein can be reduced.
Furthermore, the preset invention can be embodied without any addition of an exchange of specific information, such as notification of information on a received signal strength indicator (RSSI) at a base station to an ex system, such as a Cdma 2000 1x, for example, or without any alteration to such systems.
In the present invention, when a wireless communication module is incorporated into an information device (for example, a PDA), impedance matching with an antenna can be easily attained when the wireless communication module incorporated into the information device. Furthermore, in a communication terminal, impedance matching with an antenna can be easily attained and electric power input supplied to the antenna is minimized to effectively save electric power, resulting in an extended life of the battery. Thus, the present invention is advantageously applied in order to provide a wireless communication module, a communication terminal, and an impedance matching method.
While preferred embodiments of the invention have been described and illustrated above, it should be understood that these are exemplary of the invention and are not to be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit or scope of the present invention. Accordingly, the invention is not to be considered as being limited by the foregoing description, and is only limited by the scope of the appended claims.

Claims (8)

1. A wireless communication module for engaging in communications with a base station, the wireless communication module being incorporated into an information device having an antenna, including:
a transmitter, a transmission power being controlled by the base station;
a variable impedance matching section arranged between an antenna connector connected to the antenna and the transmitter, which adjusts an impedance by changing a matching parameter for the variable impedance matching section;
a transmission power detector for detecting the transmission power; and
a controller for adjusting the matching parameter based on the detected transmission power of the transmitter detected by the transmission power detector.
2. The wireless communication module according to claim 1, wherein the controller adjusts the matching parameter when the transmission power of the transmitter detected by the transmission power detector is stable.
3. The wireless communication module according to claim 1, further including:
an environment detector for detecting a predetermined external environment condition; and
a storage section for storing the matching parameter,
wherein the controller associates the matching parameter that has been used for the adjustment of the impedance with information on the environment detected by the environment detector and stores the matching parameter and the information into the storage section.
4. The wireless communication module according to claim 1, further including:
a storage section for storing the matching parameter,
wherein the controller obtains device-identifying information from the information device and associates the matching parameter that has been used for the adjustment of the impedance with the device-identifying information and stores the matching parameter and the device-identifying information in the storage section.
5. A communication terminal, including:
a transmit a transmission power of the transmitter being controlled by a base station;
a variable impedance matching section arranged between an antenna and the transmitter, which adjusts an impedance by changing a matching parameter for the variable impedance matching section;
a transmission power detector for detecting the transmission power; and
a controller for adjusting the matching parameter based on the detected transmission power of the transmitter detected by the transmission power detector.
6. The communication terminal according to claim 5, wherein the controller adjusts the matching parameter when the transmission power of the transmitter detected by the transmission power detector is stable.
7. The communication terminal according to claim 5, further including:
an environment detector for detecting a predetermined external environment condition; and
a storage section for storing the matching parameter,
wherein the controller associates the matching parameter that has been used for the adjustment of the impedance with information on the environment detected by the environment detector and stores the matching parameter and the information into the storage section.
8. An impedance matching method for a communications device including a transmitter, a transmission power of the transmitter being controlled by a base station; a variable impedance matching section arranged between the antenna and the transmitter, which adjusts an impedance by changing matching parameters; and a transmission power detector for detecting the transmission power, including:
performing an impedance matching by adjusting a matching parameter for the variable impedance matching section basd on a detected value of the transmission power of the transmitter detected by the transmission power detector.
US11/263,073 2004-11-01 2005-10-31 Wireless communication module, communication terminal, and impedance matching method Expired - Fee Related US7454227B2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2004318019A JP4606843B2 (en) 2004-11-01 2004-11-01 Wireless communication module, communication terminal, and impedance matching method
JP2004-318019 2004-11-01

Publications (2)

Publication Number Publication Date
US20060094458A1 US20060094458A1 (en) 2006-05-04
US7454227B2 true US7454227B2 (en) 2008-11-18

Family

ID=36262726

Family Applications (1)

Application Number Title Priority Date Filing Date
US11/263,073 Expired - Fee Related US7454227B2 (en) 2004-11-01 2005-10-31 Wireless communication module, communication terminal, and impedance matching method

Country Status (4)

Country Link
US (1) US7454227B2 (en)
JP (1) JP4606843B2 (en)
KR (1) KR100748732B1 (en)
CN (1) CN1770642B (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080273579A1 (en) * 2007-05-02 2008-11-06 Broadcom Corporation, A California Corporation Programmable antenna assembly and applications thereof
US20080280571A1 (en) * 2007-05-11 2008-11-13 Broadcom Corporation, A California Corporation RF transceiver with adjustable antenna assembly
US20090156191A1 (en) * 2007-12-14 2009-06-18 Microsoft Corporation Computing device with configurable antenna
US20100297967A1 (en) * 2007-08-31 2010-11-25 Kyocera Corporation Mobile communication terminal, and method and program for switching transmission power
US20100297957A1 (en) * 2009-05-19 2010-11-25 Broadcom Corporation Programmable antenna with configuration control and methods for use therewith
GB2476035A (en) * 2009-12-08 2011-06-15 Antenova Ltd Adaptive adjustment of RF amplifier load impedance to maximize efficiency
US20120075159A1 (en) * 2010-09-29 2012-03-29 Chia-Hao Chang Antenna matching circuit control device
US20140323065A1 (en) * 2011-01-04 2014-10-30 St-Ericsson Sa Method and Terminal Device for Automatically Tuning Impedance Matching of Multi-Frequency Band Antenna

Families Citing this family (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4786361B2 (en) * 2006-02-09 2011-10-05 京セラミタ株式会社 Image forming apparatus
KR100996104B1 (en) * 2006-12-29 2010-11-22 삼성전자주식회사 Receiving sensitivity improvement device and method for portable radio frequency identification
JP4909750B2 (en) * 2007-01-29 2012-04-04 Ｎｅｃカシオモバイルコミュニケーションズ株式会社 Wireless communication device, mobile communication terminal, and program
EP2127096A4 (en) * 2007-01-31 2012-07-11 Nokia Corp An apparatus for compensation of the impedance and the load phase of the antenna element
KR100870121B1 (en) * 2007-04-19 2008-11-25 주식회사 플라즈마트 Impedance Matching Methods And Systems Performing The Same
US9258784B2 (en) * 2007-06-28 2016-02-09 Nokia Technologies Oy Method and device for optimizing mobile radio transmitter/receiver having antenna
US20090179740A1 (en) * 2008-01-10 2009-07-16 Intermec Ip Corp. Radio frequency identification (rfid) method and apparatus for maximizing receive channel signal-to-noise ratio by adjusting phase to minimize noise
PL2272189T3 (en) * 2008-03-31 2017-08-31 Nokia Technologies Oy Antenna arrangement and test method
US8447255B2 (en) * 2008-10-28 2013-05-21 Sony Ericsson Mobile Communications Ab Variable impedance matching network and method for the same
JP2011018681A (en) * 2009-07-07 2011-01-27 Opnext Japan Inc Optical module, and method of manufacturing optical module
JP2011142559A (en) * 2010-01-08 2011-07-21 Sony Corp Power feeding device, power receiving device, and wireless feeding system
CN101964884B (en) * 2010-09-26 2014-06-11 中兴通讯股份有限公司 Method and device for self-adaptively matching antenna
TWI431935B (en) * 2010-09-28 2014-03-21 Htc Corp Antenna module
US9014645B2 (en) 2010-10-25 2015-04-21 Sharp Kabushiki Kaisha Wireless communication device, method for controlling wireless communication device, program, and storage medium
US20120154070A1 (en) * 2010-12-16 2012-06-21 Sony Ericsson Mobile Communications Ab Closed Loop Antenna Tuning Using Transmit Power Control Commands
CN102098243B (en) 2010-12-29 2016-04-13 中兴通讯股份有限公司 antenna impedance matching device and method
JP5674504B2 (en) * 2011-02-22 2015-02-25 古野電気株式会社 Antenna tuner, wireless communication system, matching circuit circuit constant setting method, and matching circuit circuit constant setting program
CN102307363B (en) * 2011-09-09 2015-05-06 京信通信系统（中国）有限公司 Standing wave detection method and apparatus thereof and base station system
CN106888036B (en) 2011-12-16 2020-02-18 英特尔公司 Wireless communication device using time-varying antenna module
KR101874892B1 (en) * 2012-01-13 2018-07-05 삼성전자 주식회사 Small antenna appartus and method for controling a resonance frequency of small antenna
KR101921494B1 (en) 2012-04-23 2018-11-23 삼성전자주식회사 Apparatus and method for matching antenna impedence in a wireless communication system
US20140065982A1 (en) 2012-09-05 2014-03-06 Seong-Youp Suh Plug-and-play time-variant antenna module for wireless communication devices
JP6121829B2 (en) * 2013-07-26 2017-04-26 株式会社東芝 ANTENNA DEVICE, RADIO COMMUNICATION DEVICE, AND CONTROL DEVICE
CN105206947A (en) * 2014-06-11 2015-12-30 中兴通讯股份有限公司 Antenna matching method and apparatus, and terminal
JP6253525B2 (en) * 2014-06-17 2017-12-27 株式会社東芝 ANTENNA DEVICE, ANTENNA AUTOMATIC MATCHING METHOD, WIRELESS DEVICE, AND CONTROL DEVICE
KR102250772B1 (en) * 2014-06-27 2021-05-11 삼성전자주식회사 Apparatas and method for preventing malfunction in an electronic device
CN108124318B (en) * 2014-09-28 2021-04-30 安科讯(福建)科技有限公司 LTE wireless network card
DE102014119259A1 (en) * 2014-12-19 2016-06-23 Intel Corporation An apparatus for providing a control signal for a variable impedance matching circuit and a method therefor
CN104577328B (en) * 2015-01-22 2017-07-18 山东大学 A kind of RFID antenna and its automatic matching method
CN105119640B (en) * 2015-08-03 2019-04-26 上海华为技术有限公司 A kind of switching method and device of antenna mode
CN107437968B (en) * 2016-05-26 2021-03-23 中兴通讯股份有限公司 Radio frequency transmitting circuit and circuit matching method
CN106656055A (en) * 2016-11-29 2017-05-10 努比亚技术有限公司 Impedance matching device and method for terminal power amplifier

Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5673001A (en) * 1995-06-07 1997-09-30 Motorola, Inc. Method and apparatus for amplifying a signal
US5880635A (en) * 1997-04-16 1999-03-09 Sony Corporation Apparatus for optimizing the performance of a power amplifier
EP1093222A1 (en) 1999-04-01 2001-04-18 Matsushita Electric Industrial Co., Ltd. Transmitter and receiver
US20020024406A1 (en) * 2000-04-28 2002-02-28 Mitsuhiro Matsumoto Phase shifter and communication device using the same
US20020085509A1 (en) * 2000-12-28 2002-07-04 Kabushiki Kaisha Toshiba Radio communication apparatus
US20030071721A1 (en) * 2001-08-04 2003-04-17 Manis Constantine N. Adaptive radiated emission control
JP2003174367A (en) 2001-09-27 2003-06-20 Toshiba Corp Portable radio equipment
KR20030069846A (en) 2002-02-22 2003-08-27 마츠시타 덴끼 산교 가부시키가이샤 Helical antenna apparatus provided with two helical antenna elements, and radio communication apparatus provided with same helical antenna apparatus
US20030199256A1 (en) * 1999-07-22 2003-10-23 Armin Klomsdorf Memory-based amplifier load adjust system
US20040008151A1 (en) * 2002-06-05 2004-01-15 Kazuhiro Kurihara Variable type antenna matching circuit
US20040198271A1 (en) * 2000-02-15 2004-10-07 Kang In Ho Envelope-tracking amplifier for improving gain, Method for improving efficiency thereof, and terminal device of mobile communication applied to the same
US20050059362A1 (en) * 2003-08-29 2005-03-17 Nokia Corporation Method and apparatus providing integrated load matching using adaptive power amplifier compensation
US20050146387A1 (en) * 2002-11-01 2005-07-07 Takeshi Toda Control unit and a control method
US6920312B1 (en) * 2001-05-31 2005-07-19 Lam Research Corporation RF generating system with fast loop control
US6961368B2 (en) * 2001-01-26 2005-11-01 Ericsson Inc. Adaptive antenna optimization network
US6993297B2 (en) * 2002-07-12 2006-01-31 Sony Ericsson Mobile Communications Ab Apparatus and methods for tuning antenna impedance using transmitter and receiver parameters

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5851453B2 (en) * 1980-09-29 1983-11-16 日本電信電話株式会社 transmitting device
JPH0969799A (en) * 1995-09-01 1997-03-11 Antenna Giken Kk Automatic control circulator device
DE19757142A1 (en) * 1997-12-20 1999-07-08 Philips Patentverwaltung Cellular device
JP3332071B2 (en) * 1998-03-05 2002-10-07 日本電気株式会社 Antenna matching adjustment circuit
DE60024225T2 (en) * 2000-03-18 2006-08-03 Siemens Ag radio transmitter
JP2001308739A (en) * 2000-04-27 2001-11-02 Kyocera Corp Radio equipment
JP2002064386A (en) * 2000-08-23 2002-02-28 Sony Corp Matching device
JP2003023429A (en) * 2001-07-09 2003-01-24 Sony Corp Radio transmitter, information equipment registration method and information equipment connection method
WO2003023955A1 (en) * 2001-09-06 2003-03-20 Matsushita Electric Industrial Co., Ltd. Array antenna apparatus
EP1298810B8 (en) * 2001-09-27 2007-12-12 Kabushiki Kaisha Toshiba Portable type radio equipment
JP3744883B2 (en) * 2002-06-05 2006-02-15 日本電気株式会社 Mobile phone, analysis device built in the same, and analysis method thereof
JP2004040556A (en) * 2002-07-04 2004-02-05 Canon Inc Information device
KR20040033917A (en) * 2002-10-16 2004-04-28 엘지전자 주식회사 A device and a operating method of controlling output power for mobile phone
JP3883955B2 (en) * 2002-11-25 2007-02-21 株式会社日立製作所 Network system, management device, information device and program
JP4155121B2 (en) * 2003-06-24 2008-09-24 日本電気株式会社 Mobile device shipping adjustment method

Patent Citations (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6020787A (en) * 1995-06-07 2000-02-01 Motorola, Inc. Method and apparatus for amplifying a signal
US5673001A (en) * 1995-06-07 1997-09-30 Motorola, Inc. Method and apparatus for amplifying a signal
US5880635A (en) * 1997-04-16 1999-03-09 Sony Corporation Apparatus for optimizing the performance of a power amplifier
EP1093222A1 (en) 1999-04-01 2001-04-18 Matsushita Electric Industrial Co., Ltd. Transmitter and receiver
KR20010043939A (en) 1999-04-01 2001-05-25 마츠시타 덴끼 산교 가부시키가이샤 Transmitter and receiver
US20030199256A1 (en) * 1999-07-22 2003-10-23 Armin Klomsdorf Memory-based amplifier load adjust system
US20040198271A1 (en) * 2000-02-15 2004-10-07 Kang In Ho Envelope-tracking amplifier for improving gain, Method for improving efficiency thereof, and terminal device of mobile communication applied to the same
US20020024406A1 (en) * 2000-04-28 2002-02-28 Mitsuhiro Matsumoto Phase shifter and communication device using the same
US20020085509A1 (en) * 2000-12-28 2002-07-04 Kabushiki Kaisha Toshiba Radio communication apparatus
US6961368B2 (en) * 2001-01-26 2005-11-01 Ericsson Inc. Adaptive antenna optimization network
US6920312B1 (en) * 2001-05-31 2005-07-19 Lam Research Corporation RF generating system with fast loop control
US20030071721A1 (en) * 2001-08-04 2003-04-17 Manis Constantine N. Adaptive radiated emission control
JP2003174367A (en) 2001-09-27 2003-06-20 Toshiba Corp Portable radio equipment
KR20030069846A (en) 2002-02-22 2003-08-27 마츠시타 덴끼 산교 가부시키가이샤 Helical antenna apparatus provided with two helical antenna elements, and radio communication apparatus provided with same helical antenna apparatus
US6806836B2 (en) 2002-02-22 2004-10-19 Matsushita Electric Industrial Co., Ltd. Helical antenna apparatus provided with two helical antenna elements, and radio communication apparatus provided with same helical antenna apparatus
US20040008151A1 (en) * 2002-06-05 2004-01-15 Kazuhiro Kurihara Variable type antenna matching circuit
US6885353B2 (en) * 2002-06-05 2005-04-26 Nec Corporation Variable type antenna matching circuit
US6993297B2 (en) * 2002-07-12 2006-01-31 Sony Ericsson Mobile Communications Ab Apparatus and methods for tuning antenna impedance using transmitter and receiver parameters
US20050146387A1 (en) * 2002-11-01 2005-07-07 Takeshi Toda Control unit and a control method
US20050059362A1 (en) * 2003-08-29 2005-03-17 Nokia Corporation Method and apparatus providing integrated load matching using adaptive power amplifier compensation

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080273579A1 (en) * 2007-05-02 2008-11-06 Broadcom Corporation, A California Corporation Programmable antenna assembly and applications thereof
US8200168B2 (en) * 2007-05-02 2012-06-12 Broadcom Corporation Programmable antenna assembly and applications thereof
US20100248650A1 (en) * 2007-05-02 2010-09-30 Broadcom Corporation Programmable antenna assembly and applications thereof
US7761061B2 (en) * 2007-05-02 2010-07-20 Broadcom Corporation Programmable antenna assembly and applications thereof
US8014732B2 (en) * 2007-05-02 2011-09-06 Broadcom Corporation Programmable antenna assembly and applications thereof
US20110310939A1 (en) * 2007-05-02 2011-12-22 Broadcom Corporation Programmable antenna assembly and applications thereof
US7933562B2 (en) * 2007-05-11 2011-04-26 Broadcom Corporation RF transceiver with adjustable antenna assembly
US20080280571A1 (en) * 2007-05-11 2008-11-13 Broadcom Corporation, A California Corporation RF transceiver with adjustable antenna assembly
US20100297967A1 (en) * 2007-08-31 2010-11-25 Kyocera Corporation Mobile communication terminal, and method and program for switching transmission power
US8606201B2 (en) 2007-08-31 2013-12-10 Kyocera Corporation Mobile communication terminal, and method and program for switching transmission power
US9780810B2 (en) * 2007-12-14 2017-10-03 Microsoft Technology Licensing, Llc Computing device with configurable antenna
US20090156191A1 (en) * 2007-12-14 2009-06-18 Microsoft Corporation Computing device with configurable antenna
US9461673B2 (en) * 2007-12-14 2016-10-04 Microsoft Technology Licensing, Llc Computing device with configurable antenna
US9172401B2 (en) * 2007-12-14 2015-10-27 Microsoft Technology Licensing, Llc Computing device with configurable antenna
US8340714B2 (en) * 2007-12-14 2012-12-25 Microsoft Corporation Computing device with configurable antenna
US20130095772A1 (en) * 2007-12-14 2013-04-18 Microsoft Corporation Computing device with configurable antenna
US8792937B2 (en) * 2007-12-14 2014-07-29 Microsoft Corporation Computing device with configurable antenna
US8190102B2 (en) * 2009-05-19 2012-05-29 Broadcom Corporation Programmable antenna with configuration control and methods for use therewith
US20100297957A1 (en) * 2009-05-19 2010-11-25 Broadcom Corporation Programmable antenna with configuration control and methods for use therewith
GB2476035B (en) * 2009-12-08 2016-06-01 Microsoft Technology Licensing Llc Improvements relating to power amplifiers and antennas
GB2476035A (en) * 2009-12-08 2011-06-15 Antenova Ltd Adaptive adjustment of RF amplifier load impedance to maximize efficiency
US8780006B2 (en) 2010-09-29 2014-07-15 Asustek Computer Inc. Antenna matching circuit control device
US8570236B2 (en) * 2010-09-29 2013-10-29 Asustek Computer Inc. Antenna matching circuit control device
TWI452850B (en) * 2010-09-29 2014-09-11 Asustek Comp Inc Antenna matching circuit control device
US20120075159A1 (en) * 2010-09-29 2012-03-29 Chia-Hao Chang Antenna matching circuit control device
US20140323065A1 (en) * 2011-01-04 2014-10-30 St-Ericsson Sa Method and Terminal Device for Automatically Tuning Impedance Matching of Multi-Frequency Band Antenna
US9160395B2 (en) * 2011-01-04 2015-10-13 ST-Ericsson Semiconductor (Beijing) Co., Ltd Method and terminal device for automatically tuning impedance matching of multi-frequency band antenna

Also Published As

Publication number Publication date
KR20060052270A (en) 2006-05-19
JP2006129358A (en) 2006-05-18
CN1770642A (en) 2006-05-10
JP4606843B2 (en) 2011-01-05
KR100748732B1 (en) 2007-08-13
US20060094458A1 (en) 2006-05-04
CN1770642B (en) 2011-05-18

Similar Documents

Publication Publication Date Title
US7454227B2 (en) Wireless communication module, communication terminal, and impedance matching method
EP2469941B1 (en) Wireless local-area access network routing device and signal transmission method
EP2311194B1 (en) Closed loop auto antenna tuning for wireless communications
US8923779B2 (en) Systems and methods for tuning an antenna for a frequency modulation transceiver
US7529528B2 (en) Power consumption controlling apparatus for high frequency amplifier
US8831529B2 (en) Wireless communications circuitry with temperature compensation
US8086268B2 (en) Mobile communication terminal and method of controlling transmission characteristic thereof
EP2182641B1 (en) Electronic devices with calibrated radio frequency communications circuitry
US20080111748A1 (en) Antenna system having plural selectable antenna feed points and method of operation thereof
US20110269416A1 (en) Transmitter
CN101133560A (en) Mobile station traffic state antenna tuning systems and methods
US20100311423A1 (en) Communication Terminal Out of Range Determination Method, Wireless Communication System Switching Method and Communication Terminal
US20130165057A1 (en) Rf transmission circuit and electronic device and method for saving power thereof
US20190230593A1 (en) Positioning system and positioning method
US20120231737A1 (en) Energy distribution among antennas in an antenna system
CN108832944B (en) Power compensation method, device, terminal equipment and storage medium
JPH11136157A (en) Mobile radio terminal equipment
JP2003174367A (en) Portable radio equipment
US7551890B2 (en) Method for reducing the radiation load by a mobile radio terminal with directional emission, and a mobile radio terminal with directional emission
JPWO2003015294A1 (en) Portable radio
KR20070033509A (en) Apparatus and method for reducing hand effect of terminal having internal type antenna
JP3834492B2 (en) Battery saving method, mobile device, and battery saving processing program recording storage medium
KR20070094223A (en) Apparatus and method for power management in mobile communication terminal
EP1622262B1 (en) RF unit and method for power control to be used in a radio communication equipment
US20040029539A1 (en) Receiver

Legal Events

Date Code Title Description
AS Assignment

Owner name: KYOCERA CORPORATION, JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:KITAJI, MITSUHIRO;REEL/FRAME:017333/0036

Effective date: 20051130

FEPP Fee payment procedure

Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

FPAY Fee payment

Year of fee payment: 4

AS Assignment

Owner name: HANEI CORPORATION, NEW HAMPSHIRE

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:KYOCERA CORPORATION;REEL/FRAME:029569/0371

Effective date: 20121019

REMI Maintenance fee reminder mailed
LAPS Lapse for failure to pay maintenance fees
STCH Information on status: patent discontinuation

Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362

FP Lapsed due to failure to pay maintenance fee

Effective date: 20161118